Comparative Study on Leaf Morphology-Venation Pattern of Hedyotis auricularia L. and Its Adulterants.

[Objectives] To compare the leaf morphology and leaf venation patterns of Hedyotis auricularia L. and its adulterants, such as Mitracarpus hirtus (L.) DC., Spermacoce pusilla Wall, and Spermacoce alata Aubl., produced in Guangxi, so as to provide a simple and rapid identification method for the identification of H. auricularia L. in Guangxi. [Methods] LMVP (leaf morphology-venation pattern) identification method was used to study the characteristics of leaf morphology-venation pattern. [Results] Characteristics of leaf morphology-venation pattern; (i) H. auricularia L.; circular knotted-curved pinnate leaf venation without reaching the margin; the primary veins run straight without branches, the number of secondary' veins is 5 to 9, and the angles included in tertiary veins are mostly near right angles or obtuse angles. (ii) M. hirtus (L.) DC.; curved pinnate leaf venation without reaching the margin; the primary veins run straight without obvious changes, the number of secondary' veins is 3 to 5, and the tertiary veins are slender, and the included angles are mostly acute. (iii) S. pusilla Wall.; curved leaf venation without reaching the leaf margin; there are4 to 5 pairs of secondary veins, most of which are opposite; the angle between the secondary veins and the primary' veins in the middle and near the petiole is mostly medium acute angle, and the extension of the tertiary veins has no fixed direction, (iv) S. alata Aubl.; circular knotted-curved pinnate leaf venation; the primary veins are convex and straight without branches, and there are 4 to 6 pairs of secondary veins, alternating. The angle between secondary' veins and primary veins is mostly medium acute angle, the angle between tertiary' veins and secondary veins is near right angle, and the tertiary veins are mostly transversely extended. [Conclusions] The leaf morphology-venation patterns of the above-mentioned H. auricularia L. and M. hirtus (L.) DC., S. pusilla Wall., and S. alata Aubl. can be used as their identification features, and the identification method has certain operability, which provides an identification idea for the identification of Chinese herbal medicines. [ABSTRACT FROM AUTHOR]